The antitumor capability of aminoxyl radicals (sometimes referred to as nitroxyl radicals) has been demonstrated by many investigators. One recent publication that provides a review of the role of these radicals in cancer chemotherapy is Zhdanov, R. I., (editor), Bioactive Spin Labels, pages 429-460, Springer-Verlag, New York, 1992.
There have been many attempts to deliver these radicals for anticancer purposes. In one method, low molecular weight compounds have been used to administer these radicals without coadministration of conventional anticancer agents. In another method, conventional anticancer agents modified to contain aminoxyl-containing radicals have been utilized. Neither of these approaches has as yet found acceptance.
Turning now to another area, low molecular weight compounds containing aminoxyl-containing radicals have been utilized to sensitize cells including tumor cells to the effects of ionizing radiation, thereby increasing the efficiency and result of the radiation therapy. This method has not yet found acceptance.
Turning now to still another area, the major obstacle to using existing synthetic biomaterials for the reconstruction of injured, diseased or aged blood vessels is the formation of blood clots on these synthetic biomaterials after implantation, causing plugging of the artificial vessels and rendering them useless. Thus, there is a need for synthetic materials for blood vessel reconstruction which reduce the probability of blood clot formation.